kstrto*: accept "-0" for signed conversion

strtol(3) et al accept "-0", so should we.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 2 insertions, 6 deletions

diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index ec8da78df9be..94be244e8441 100644
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -152,7 +152,7 @@ int kstrtoll(const char *s, unsigned int base, long long *res)
                 rv = _kstrtoull(s + 1, base, &tmp);
                 if (rv < 0)
                         return rv;
-                if ((long long)(-tmp) >= 0)
+                if ((long long)-tmp > 0)
                         return -ERANGE;
                 *res = -tmp;
         } else {
diff --git a/lib/test-kstrtox.c b/lib/test-kstrtox.c
index 4137bca5f8e8..f355f67169b6 100644
--- a/lib/test-kstrtox.c
+++ b/lib/test-kstrtox.c
@@ -260,6 +260,7 @@ static void __init test_kstrtoll_ok(void)
                 {"4294967297",  10,     4294967297LL},
                 {"9223372036854775807", 10,     9223372036854775807LL},
 
+                {"-0",  10,     0LL},
                 {"-1",  10,     -1LL},
                 {"-2",  10,     -2LL},
                 {"-9223372036854775808",        10,     LLONG_MIN},
@@ -277,11 +278,6 @@ static void __init test_kstrtoll_fail(void)
                 {"-9223372036854775809",        10},
                 {"-18446744073709551614",       10},
                 {"-18446744073709551615",       10},
-                /* negative zero isn't an integer in Linux */
-                {"-0",  0},
-                {"-0",  8},
-                {"-0",  10},
-                {"-0",  16},
                 /* sign is first character if any */
                 {"-+1", 0},
                 {"-+1", 8},